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排序方式: 共有383条查询结果,搜索用时 15 毫秒
101.
The authors addressed the role and the management of pain in Paget's disease by a retrospective study. The objectives were: to assess the presence of pain in Paget's disease; to look for a relationship between pain and the levels of total alkaline phosphatase (total ALP); to verify if the most commonly used drugs in Paget's disease, calcitonin and bisphosphonates, were able to reduce the pain and the levels of total ALP. The study analyzed 107 Italian patients with Paget's disease who were hospitalized at the same Institute between 1970 and 2010; all patients affected by severe arthritis were excluded. From the analysis of the clinical records it emerged that as many as 85% of patients had pain and that total ALP was also increased in most of the patients with pain in comparison with patients without pain. The clinical and metabolic effects of different therapies were then assessed: many patients had not received any specific therapy (58%), others had been treated with calcitonin (25%) and others with bisphosphonates (17%). In fact, the patients treated with bisphosphonates had significantly lower levels both of pain and total ALP. The authors hypothesize that the pain in Paget's disease has a primary origin and is correlated to the degree of bone metabolic hyperactivity. Finally, treatment with bisphosphonates appeared to be the most appropriate treatment, having been able to control both the pain and the metabolic hyperactivity. 相似文献
102.
The C-terminal β-hairpin of RNase A contains a turn with a cis Asn113-Pro114 peptide bond. Pioneering pulsed HX experiments have shown that the C-terminal β-hairpin forms early during refolding. This is puzzling since the Asn113-Pro114 bond is predominately trans at this stage and this conformation destabilizes the native monomer. RNase A, when refolded at high concentration, forms a series of 3D domain-swapped oligomers. In the oligomers formed by C-terminal β-strand swapping, Asn113-Pro114 is trans and permits the formation of a new intersubunit β-sheet. We hypothesize that oligomeric species with trans Asn113-Pro114 may form during refolding. Such species could account for the HX results while comfortably accommodating Asn113-Pro114 in the trans conformation. Here, we test this hypothesis by employing chromatographic methods to detect oligomers forming in refolding conditions and find significant amounts of dimer. We propose that a 3D domain-swapped dimeric intermediate provides a minor alternative pathway for RNase A refolding. 相似文献
103.
Bruzzese F Leone A Rocco M Carbone C Piro G Caraglia M Di Gennaro E Budillon A 《Journal of cellular physiology》2011,226(9):2378-2390
104.
p66(ShcA) and oxidative stress modulate myogenic differentiation and skeletal muscle regeneration after hind limb ischemia 总被引:1,自引:0,他引:1
Zaccagnini G Martelli F Magenta A Cencioni C Fasanaro P Nicoletti C Biglioli P Pelicci PG Capogrossi MC 《The Journal of biological chemistry》2007,282(43):31453-31459
Oxidative stress plays a pivotal role in ischemic injury, and p66(ShcA)ko mice exhibit both lower oxidative stress and decreased tissue damage following hind limb ischemia. Thus, it was investigated whether tissue regeneration following acute hind limb ischemia was altered in p66(ShcA)ko mice. Upon femoral artery dissection, muscle regeneration started earlier and was completed faster than in wild-type (WT) control. Moreover, faster regeneration was associated with decreased oxidative stress. Unlike ischemia, cardiotoxin injury induced similar skeletal muscle damage in both genotypes. However, p66(ShcA)ko mice regenerated faster, in agreement with the regenerative advantage upon ischemia. Since no difference between p66(ShcA)wt and knock-out (ko) mice was found in blood perfusion recovery after ischemia, satellite cells (SCs), a resident population of myogenic progenitors, were examined. Similar SCs numbers were present in WT and ko mice. However, in vitro cultured p66(ShcA)ko SCs displayed lower oxidative stress levels and higher proliferation rate and differentiated faster than WT. Furthermore, when exposed to sublethal H(2)O(2) doses, p66(ShcA)ko SCs were resistant to H(2)O(2)-induced inhibition of differentiation. Finally, myogenic conversion induced by MyoD overexpression was more efficient in p66(ShcA)ko fibroblasts compared with WT. The present work demonstrates that oxidative stress and p66(ShcA) play a crucial role in the regenerative pathways activated by acute ischemia. 相似文献
105.
Amigó M Terencio MC Payá M Iodice C De Rosa S 《Bioorganic & medicinal chemistry letters》2007,17(9):2561-2565
Semisynthesis of 13 new thio avarol derivatives (4-16) and in vitro evaluation on the photodamage response induced by UVB irradiation are described. Their ability to inhibit NF-kappaB activation and TNF-alpha generation in HaCaT cells as well as their antioxidant capacity in human neutrophils has also been studied. Among them we have identified two monophenyl thio avarol derivatives (4-5) lacking cytotoxicity which can be considered promising UVB photoprotective agents through the potent inhibition of NF-kappaB activation with a mild antioxidant pharmacological profile. 相似文献
106.
Bovine seminal ribonuclease (BS-RNase) is made up of two identical subunits bridged through two disulfide bonds. In solution, it exists as a 2:1 equilibrium mixture between two forms, with (MxM) and without swapping (M=M) of the N-terminal arms. The swapping endows BS-RNase with some special biological functions, including antitumor activity, since MxM retains a dimeric structure even under reducing conditions, thus evading the cytosolic ribonuclease inhibitor. To investigate the structural basis of domain swapping in BS-RNase, we have obtained several mutants by replacing selected residues with the corresponding ones of its monomeric counterpart, bovine pancreatic ribonuclease (RNase A). We have already shown that, in contrast with all other cases of swapped proteins, the swapping propensity of BS-RNase does not depend on the specific sequence of the 16-22 hinge loop, which connects the main body to the dislocating arm. In this paper we report the design, the expression, and the structural characterization of two mutants obtained by replacing Arg80 with Ser either in BS-RNase or in the mutant already containing the 16-22 hinge sequence of RNase A. NMR and circular dichroism data indicate that, in the monomeric form of the latter mutant, Ser80 acts as a switch for the conformation of the hinge region. Accordingly, in the dimeric form of the same mutant the MxM:M=M equilibrium ratio is inverted to 1:2. Overall, these data suggest that the presence of Arg80 triggers the swapping of N-terminal ends and plays a relevant role in the stability of the swapped form of BS-RNase. 相似文献
107.
Reverse signaling through GITR ligand enables dexamethasone to activate IDO in allergy 总被引:8,自引:0,他引:8
Grohmann U Volpi C Fallarino F Bozza S Bianchi R Vacca C Orabona C Belladonna ML Ayroldi E Nocentini G Boon L Bistoni F Fioretti MC Romani L Riccardi C Puccetti P 《Nature medicine》2007,13(5):579-586
Glucocorticoid-induced tumor necrosis factor receptor (GITR) on T cells and its natural ligand, GITRL, on accessory cells contribute to the control of immune homeostasis. Here we show that reverse signaling through GITRL after engagement by soluble GITR initiates the immunoregulatory pathway of tryptophan catabolism in mouse plasmacytoid dendritic cells, by means of noncanonical NF-kappaB-dependent induction of indoleamine 2,3-dioxygenase (IDO). The synthetic glucocorticoid dexamethasone administered in vivo activated IDO through the symmetric induction of GITR in CD4(+) T cells and GITRL in plasmacytoid dendritic cells. The drug exerted IDO-dependent protection in a model of allergic airway inflammation. Modulation of tryptophan catabolism via the GITR-GITRL coreceptor system might represent an effective therapeutic target in immune regulation. Induction of IDO could be an important mechanism underlying the anti-inflammatory action of corticosteroids. 相似文献
108.
109.
Roshani Patel Cvetelin Vasilev Daniel Beck Carmine G. Monteferrante Jan Maarten van Dijl C. Neil Hunter Corinne Smith Colin Robinson 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
The Tat system transports folded proteins across the bacterial plasma membrane. The mechanism is believed to involve coalescence of a TatC-containing unit with a separate TatA complex, but the full translocation complex has never been visualised and the assembly process is poorly defined. We report the analysis of the Bacillus subtilis TatAyCy system, which occurs as separate TatAyCy and TatAy complexes at steady state, using single-particle electron microscopy (EM) and advanced atomic force microscopy (AFM) approaches. We show that a P2A mutation in the TatAy subunit leads to apparent super-assembly of Tat complexes. Purification of TatCy-containing complexes leads to a large increase in the TatA:TatC ratio, suggesting that TatAyP2A complexes may have attached to the TatAyCy complex. EM and AFM analyses show that the wild-type TatAyCy complex purifies as roughly spherical complexes of 9–16 nm diameter, whereas the P2A mutation leads to accumulation of large (up to 500 nm long) fibrils that are chains of numerous complexes. Time lapsed AFM imaging, recorded on fibrils under liquid, shows that they adopt a variety of tightly curved conformations, with radii of curvature of 10–12 nm comparable to the size of single TatAyP2A complexes. The combined data indicate that the mutation leads to super-assembly of TatAyP2A complexes and we propose that an individual TatAyP2A complex assembles initially with a TatAyP2ACy complex, after which further TatAyP2A complexes attach to each other. The data further suggest that the N-terminal extracytoplasmic domain of TatAy plays an essential role in Tat complex interactions. 相似文献
110.
Giovanni Tarantino Susan Costantini Carmine Finelli Francesca Capone Eliana Guerriero Nicolina La Sala Saverio Gioia Giuseppe Castello 《PloS one》2014,9(9)